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    Re: iSCSI: INQUIRY page 0x83 identifier



    
    JP,
    
    The identifier in this page of Inquiry is NOT at the 'target device' or
    'iSCSI device' layer.  It is an identifier for the logical unit to which
    the inquiry command was sent.  The FC format was meant primarily for FC
    disk drives that have only one logical unit (though it can be used in some
    ways by FC controllers, etc.).
    
    The Device (as in a container of one or more logical units) identifier is
    yet to be fully defined in SCSI, which is one reason that iSCSI NDT chose
    to define such a name for the iSCSI device.
    
    As for an iSCSI type or format for logical unit identifiers:
    1) SCSI already allows for an ascii formatted identifier (typically this
    includes vendor, model, serial number). Since NDT has defined WWUIs for
    DEVICES and these have a defined UTF-8 format, there is nothing to
    *prevent* a vendor from using these strings as the starting point for LU
    page 83 identifiers of the logical units within that device.
    2) But..., iSCSI and NDT should not attempt to make a rule under which
    these are used.  FC's intervention in this was more as a strong suggestion,
    and is certainly not a requirement.
    
    Did I confuse things even more?
    
    Jim Hafner
    
    
    Raghavendra Rao <jp.raghavendra@sun.com>@ece.cmu.edu on 01/23/2001 08:02:05
    AM
    
    Please respond to Raghavendra Rao <jp.raghavendra@sun.com>
    
    Sent by:  owner-ips@ece.cmu.edu
    
    
    To:   ips@ece.cmu.edu
    cc:
    Subject:  iSCSI: INQUIRY page 0x83 identifier
    
    
    
    
    This may seem like a T10 issue at a high level, but I'm concerned that
    SPC-2 (SCSI primary command set) defines in the INQUIRY page 0x83
    identifier
    type field, a FC identifier type (value = 3).
    
    What identifer type should an iSCSI target use to report a LU identifier
    when queried for page 0x83 ? Luckily there seem to be a generic IEEE
    extended identifier type (value = 2).
    
    Is the naming and discovery document going to provide a clear defintion
    about LU names ? I understand that there should be NO interconnect specific
    identifier at the SCSI layer - But SPC-2 is already polluted with a FC
    identifier type.
    
    -JP
    
    
    
    
    


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Last updated: Tue Sep 04 01:05:45 2001
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